In air conditioning systems such as those used in motor vehicles, it is common practice to employ an accumulator-dehydrator assembly to ensure delivery of the refrigerant in a vapor phase to the compressor and remove any water from circulation. Moreover, where oil is also circulated for lubrication of the compressor, it is desirable that it be maintained in the vapor flow to the compressor. A design found highly efficient in meeting these various requirements is that disclosed in U.S. Pat. No. 4,331,001 assigned to the assignee of the present invention. And then there is U.S. Pat. No. 4,509,340 which proposes improvements thereof directed toward fewer parts and easier assembly. In particular, the latter design proposes forming the desiccant canister with an integral outlet fitting that projects into and sealingly engages the outlet of the accumulator housing. It has been discovered that while this approach does have certain part reduction and assembly benefits, there is then required special provision for assembling a particulate filter at the entrance to the outlet fitting internal of the canister. This is made possible in the above noted integral outlet fitting and canister design by additionally forming the desiccant canister of two halves which must be brought together and joined about the particulate filter.